Flash Communication: Synthesis and Characterization of an Iron(V) Thiolate Complex

Thiolate-ligated high-valent iron species are reactive intermediates in the C–H bond activation reactions of P450 and isopenicillin N synthase enzymes. Synthetic complexes of the type are rarely known. Presented herein are the synthesis and characterization of an iron­(V) bisimido complex with thiolate ligation, viz. [(IPr)­Fe­(NC­(CH3)2Ph)2(2-F-C6H4S)] (1, IPr = 1,3-bis­(2′,6′-diisopropylphenyl)­imidazol-2-ylidene) as well as the ionic iron­(V) bisimido complex [(IPr)­Fe­(NC­(CH3)2Ph)2]­[BArF4] (2, BArF4 = tetra­(3,5-ditrifluoromethylphenyl)­borate). The two iron­(V) complexes have been characterized by a single-crystal X-ray diffraction study and EPR and zero-field 57Fe Mössbauer spectroscopy. The spectroscopic data and DFT calculations revealed their S = 1/2 ground spin states.